CN116173735A - Bipolar membrane electrodialysis concentration system - Google Patents

Abstract

The invention belongs to the technical field of electrodialysis equipment, and discloses a bipolar membrane electrodialysis concentration system, which comprises a partition electrodialysis module, a liquid supply pipeline and an electric control system, wherein the liquid supply pipeline and the electric control system are respectively connected with the partition electrodialysis module, the liquid supply pipeline is connected with the partition electrodialysis module for liquid import/export, and the electric control system is connected with the partition electrodialysis module for power supply; the partition electrodialysis module comprises a fixed structure and an electrode plate, wherein the electrode plate comprises a plurality of positive plates and negative plates which are paired and connected with an electric control system, and a plurality of unipolar partitions are arranged between the adjacent positive plates and negative plates; the monopolar separator is provided with a volume groove which is open towards one side, an ion exchange membrane is arranged at the bottom of the volume groove, the polarities of the ion exchange membranes on the adjacent monopolar separators are opposite, and the volume groove is communicated with the liquid supply pipeline to realize liquid flow; a hard pressing strip is arranged between the monopole partition plates, and the pressing strip is matched with the edge of the volume groove to be pressed tightly so as to realize sealing.

Description

Bipolar membrane electrodialysis concentration system

Technical Field

The invention belongs to the technical field of electrodialysis treatment equipment, and particularly relates to a bipolar membrane electrodialysis concentration system.

Background

Electrodialysis is a method of separating different solute particles (e.g., ions) by using the selective permeability of a semipermeable membrane, and when dialysis is performed under an electric field, charged solute particles (e.g., ions) in a solution migrate through the membrane, and a technique of purifying and separating substances by using electrodialysis is called electrodialysis. The technology is initially used for sea water desalination, is widely used in chemical industry, light industry, metallurgy, papermaking and medicine industry, and is especially used for preparing pure water and treating three wastes in environmental protection, such as acid-base recovery, electroplating waste liquid treatment, recovery of useful substances from industrial waste water and the like.

Electrodialysis is a combination of electrochemical and dialysis diffusion processes; under the drive of an externally applied direct current electric field, the selective permeability of the ion exchange membrane (namely cations can permeate the cation exchange membrane and anions can permeate the anion exchange membrane) is utilized, and the anions and the cations respectively move to the anode and the cathode. In the ion migration process, if the fixed charge of the membrane is opposite to the charge of the ions, the ions can pass through; if the charges of the ions are the same, the ions are repelled, so that the purposes of solution desalination, concentration, refining or purification and the like are realized.

The existing electrodialysis concentration treatment equipment is similar in principle, is provided with electrode separators, electrode plates and an external fixing and pipe conveying system, and is characterized in that a cavity is formed between the electrode separators, and a plurality of spaces with different functions, namely a concentration cavity and a clear water cavity, are formed on a plurality of channels for liquid to flow between the electrode plates by arranging the electrode separators with different polarities. By continuously introducing high-salt sewage into the cavities, the polar attraction ions are formed by discharging the electrode plates of two stages to approach, and the electrode separators with different polarities limit the movement of the ions to take effect. Because the device is used for better dialysis concentration effect under the condition of lower electricity consumption in industry, thinner baffle materials are adopted, a plurality of smaller cavities are formed in a multi-piece laminating mode to contain sewage, and water is supplied through a pipe conveying device to realize automatic electrodialysis.

In the prior art, the electrode separator is mostly made of PVC or other high polymer materials, has smaller thickness, and is tensioned and fixed through an external fixing structure after being aligned and attached by a plurality of sheets. However, when the material is thin and has a large area, the material is easy to deform during installation or use. In addition, most of the existing assembly modes are manually assembled, namely, people manually put one by one on the same fixing frame to fix the fixing frame, and the mode can cause unstable sealing effect and can cause leakage. This technical problem is usually solved by covering the surface with a sealing film or other material or by gluing after assembly. However, this approach is unavoidable because there is a channel that is not in communication with the liquid in the individual electrode separator chambers, such as concentrate into the clean water chamber, even though the external seal is leak-free, internal local leaks can lead to failure of the entire apparatus, reducing the processing efficiency of the entire apparatus. Or after part of liquid leaks, leakage current occurs, and the electricity consumption is increased.

Disclosure of Invention

In order to solve the problems in the prior art, the invention provides a bipolar membrane electrodialysis concentration system, which improves the waterproof effect of the bipolar membrane electrodialysis concentration system by improving the partition plate structure of the bipolar membrane electrodialysis concentration system, and avoids leakage caused by assembly problems when a plurality of thinner monopolar partition plates are adopted.

The technical scheme adopted by the invention is as follows:

in a first aspect, the invention provides a bipolar membrane electrodialysis concentration system, which comprises a partition electrodialysis module, a liquid supply pipeline and an electric control system, wherein the liquid supply pipeline and the electric control system are respectively connected with the partition electrodialysis module, the liquid supply pipeline is connected with the partition electrodialysis module for liquid import/export, and the electric control system is connected with the partition electrodialysis module for power supply;

the partition electrodialysis module comprises a fixed structure and an electrode plate, wherein the electrode plate comprises a plurality of positive plates and negative plates which are paired and connected with an electric control system, and a plurality of unipolar partitions are arranged between the adjacent positive plates and negative plates;

the monopolar separator is provided with a volume groove which is open towards one side, an ion exchange membrane is arranged at the bottom of the volume groove, the polarities of the ion exchange membranes on the adjacent monopolar separators are opposite, and the volume groove is communicated with the liquid supply pipeline to realize liquid flow;

a hard pressing strip is arranged between the monopole partition plates, and the pressing strip is matched with the edge of the volume groove to be pressed tightly so as to realize sealing.

With reference to the first aspect, the present invention provides a first implementation manner of the first aspect, wherein the monopole separator has a soft deformation area near the edge of the volume groove, and the pressing strip has a portion for pressing the deformation area when the monopole separators are buckled and is in contact with at least 40% of the deformation area for pressing deformation sealing through the portion.

With reference to the first implementation manner of the first aspect, the present invention provides a second implementation manner of the first aspect, the monopolar separator is provided with a sink groove between the edge of the volume groove (5) and the edge of the monopolar separator, and the deformation area is soft insulating material filled in the sink groove;

when a plurality of monopole baffle plates are buckled, the pressing strips penetrate into the sinking grooves to squeeze the deformation areas, and the contact area between the pressing strips and the deformation areas is 40% -70%.

With reference to the first embodiment of the first aspect, the present invention provides a third embodiment of the first aspect, wherein the deformation area is an area where a drop is formed by an edge of the volume groove, and a contact area between the pressing bar and the deformation area is 50-80%;

when the monopole partition plates are buckled, the outer side edge of the pressing strip does not exceed the outer side of the deformation area, the inner side edge of the pressing strip is positioned in the volume groove, and the thickness of the pressing strip is smaller than the depth of the volume groove.

With reference to the third implementation manner of the first aspect, the present invention provides a fourth implementation manner of the first aspect, wherein the deformation region has a first inclined plane, the pressing bar has a second inclined plane corresponding to the deformation region, and the first inclined plane contacts with the second inclined plane when the pressing bar presses the deformation region.

With reference to the first implementation manner of the first aspect, the present invention provides a fifth implementation manner of the first aspect, wherein the deformation area is a sealing strip disposed at an inner bottom of the volume groove and close to an edge of the volume groove, and the pressing strip is completely immersed into the volume groove and is in contact with the sealing strip for extrusion when the plurality of monopole separators are buckled, and a contact area between the pressing strip and a surface of the sealing strip is 40-50%.

With reference to the fifth implementation manner of the first aspect, the present invention provides a sixth implementation manner of the first aspect, a gap between the pressing strip and the bottom of the volume groove when the plurality of monopole separators are buckled is d, and a height of the sealing strip is 2d and is smaller than a depth of the volume groove.

With reference to the several embodiments of the first aspect, the present invention provides a seventh embodiment of the first aspect, the monopole separator is a plate body made of a soft material, a hard plate layer is disposed between adjacent monopole separators, and the batten is disposed on the hard plate layer.

With reference to the several embodiments of the first aspect, the invention provides an eighth embodiment of the first aspect, where the monopolar separator is a multilayer structure and at least includes a soft separator and a hard plate layer, the volume tank is an opening in the middle of the soft separator, the hard plate layer is provided with a plurality of through holes at the opening of the soft separator, and the ion exchange membrane is attached to the through holes and fixed by edge sealing of the soft separator;

the bead is disposed on the stiff plate layer and protrudes in a direction opposite the volume groove.

With reference to the eighth implementation manner of the first aspect, the present invention provides a ninth implementation manner of the first aspect, where the monopolar separator is provided with a plurality of water permeable holes with central symmetry on two sides of the volume tank, and the water permeable hole on one side includes a first water permeable hole and a second water permeable hole that are arranged at intervals, where the second water permeable hole has a plurality of diversion slots that are communicated with an edge of an adjacent side of the volume tank, and the edge of one side of the volume tank is divided into a plurality of short sides by the plurality of diversion slots that are arranged at intervals;

the pressing strips comprise long pressing strips corresponding to the adjacent edges of the volume grooves and not pressed by the water permeable holes, and short pressing strips corresponding to the short sides of the volume grooves;

the end part of the long pressing strip is provided with an expansion end, and a deformation area corresponding to the expansion end is arranged on the soft interlayer.

The beneficial effects of the invention are as follows:

(1) According to the invention, the pressing strips are arranged between the monopole partition plates and are matched with the volume grooves arranged in the monopole partition plates, so that the monopole partition plates are extruded and deformed with the deformation areas of the volume grooves to form a good sealing effect, even if a manual assembly mode is adopted, each monopole partition plate is only required to be aligned and installed on a die or guide equipment, and each monopole partition plate is limited, extruded and sealed by the pressing strips after being pressed by an external fixing structure;

(2) According to the invention, by optimizing the position of the deformation region and the matching position of the pressing strip, a stable extrusion effect can be provided in the process of alignment extrusion, and a gap is formed on one side of the extrusion device for the movement of the extruded material of part of the deformation region to the side space;

(3) According to the invention, the sealing strip structure is matched with the pressing strip in an optimized manner, a non-extrudable deformed monopole partition plate structure can be adopted, a circle of sealing strip is formed at the side wall of the volume groove, so that the sealing effect can be realized by matching with the pressing strip, the process difficulty is low, the sealing effect is stable, and the poor pressure bearing performance caused by adopting a soft monopole partition plate is avoided;

(4) According to the invention, by arranging the monopole baffle plate structure with the multilayer structure, corresponding effects can be realized through different material characteristics when the monopole baffle plate structure is mutually extruded, meanwhile, the ion exchange membrane is convenient to arrange, integral extrusion molding is not needed, and the process difficulty and the manufacturing cost are reduced;

(5) According to the invention, the short pressing strips and the long pressing strips are matched at the water permeable holes, so that the problem that leakage easily occurs between the diversion fine grooves arranged at intervals due to smaller size can be improved through the short pressing strips at the edges of the volume grooves at one side of the water permeable holes according to the characteristics of the volume grooves; meanwhile, the long pressing strips can be adapted to the edges without water permeable holes, particularly when a plurality of monopole partition plates are installed, deformation leakage points are easy to appear on the longer edges of the long pressing strips, and good sealing effect and positioning effect are formed at the end parts through the expansion ends of the long pressing strips.

Drawings

FIG. 1 is an isometric view of an entire electrodialysis concentration system in an embodiment of the invention;

FIG. 2 is a side view of the entire electrodialysis concentration system in an embodiment of the invention;

FIG. 3 is a schematic front view of a single monopolar separator plate in an embodiment of the present invention;

FIG. 4 is a first isometric view of a single monopolar separator plate in an embodiment of the present invention;

FIG. 5 is a schematic side view of a single monopolar separator plate in an embodiment of the present invention;

FIG. 6 is a second axial schematic view of a single monopolar separator plate in an embodiment of the present invention;

FIG. 7 is a schematic front view of a single monopolar separator plate with a pinch strip in phantom in an embodiment of the present invention;

FIG. 8 is a schematic view of a first edge of two monopolar separators in a partially unattached state in accordance with an embodiment of the present invention;

FIG. 9 is a schematic view of a first edge portion of two monopolar separators in a partially conformed state according to an embodiment of the present invention;

FIG. 10 is a schematic view of a second edge of two monopolar separators in a partially unattached state in accordance with an embodiment of the present invention;

FIG. 11 is a schematic view of a third edge portion of two monopolar separators in a partially unattached state in accordance with an embodiment of the present invention;

fig. 12 is a schematic view of a third edge partially bonded condition of two monopolar separators according to an embodiment of the present invention.

In the figure: 1-external fixing frame, 2-electrode plate, 3-tension rod, 4-monopole baffle, 4.1-soft interlayer, 4.2-hard plate layer, 5-volume groove, 6-first water permeable hole, 7-second water permeable hole, 8-diversion fine groove, 9-long press bar, 10-short press bar and 11-sealing strip.

Detailed Description

The invention is further illustrated by the following description of specific embodiments in conjunction with the accompanying drawings.

For the purposes of making the objects, technical solutions and advantages of the embodiments of the present application more clear, the technical solutions of the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application, and it is apparent that the described embodiments are some embodiments of the present application, but not all embodiments. The components of the embodiments of the present application, which are generally described and illustrated in the figures herein, may be arranged and designed in a wide variety of different configurations.

Thus, the following detailed description of the embodiments of the present application, as provided in the accompanying drawings, is not intended to limit the scope of the application, as claimed, but is merely representative of selected embodiments of the application. All other embodiments, which can be made by one of ordinary skill in the art without undue burden from the present disclosure, are within the scope of the present disclosure.

It should be noted that: like reference numerals and letters denote like items in the following figures, and thus once an item is defined in one figure, no further definition or explanation thereof is necessary in the following figures.

In the description of the present application, it should be noted that, if the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," "outer," and the like indicate an azimuth or a positional relationship based on that shown in the drawings, or an azimuth or a positional relationship that a product of the application conventionally puts in use, it is merely for convenience of describing the present application and simplifying the description, and does not indicate or imply that the device or element to be referred to must have a specific azimuth, be configured and operated in a specific azimuth, and thus should not be construed as limiting the present application. Furthermore, the terms "first," "second," and the like in the description of the present application, if any, are used for distinguishing between the descriptions and not necessarily for indicating or implying a relative importance.

Furthermore, the terms "horizontal," "vertical," and the like in the description of the present application, if any, do not denote a requirement that the component be absolutely horizontal or overhang, but rather may be slightly inclined. As "horizontal" merely means that its direction is more horizontal than "vertical", and does not mean that the structure must be perfectly horizontal, but may be slightly inclined.

In the description of the present application, it should also be noted that, unless explicitly stated and limited otherwise, the terms "disposed," "mounted," "connected," and "connected" should be construed broadly, and may be, for example, fixedly connected, detachably connected, or integrally connected; can be mechanically or electrically connected; can be directly connected or indirectly connected through an intermediate medium, and can be communication between two elements. The specific meaning of the terms in this application will be understood by those of ordinary skill in the art in a specific context.

Example 1:

the embodiment discloses a bipolar membrane electrodialysis concentration system which is used for concentrating high-salt wastewater and simultaneously producing acid and alkali.

The electrodialysis concentration system comprises a partition electrodialysis module, a liquid supply pipeline and an electric control system, wherein the liquid supply pipeline and the electric control system are respectively connected with the partition electrodialysis module, the liquid supply pipeline is connected with the partition electrodialysis module for liquid import/export, and the electric control system is connected with the partition electrodialysis module for power supply.

Wherein the electrodialysis module has several, as shown in fig. 1 and 2, the module comprises an external fixing frame 1 and an electrode plate 2, the electrode plate 2 comprises several positive and negative plates which are paired and connected with an electric control system, and several monopolar separators 4 are arranged between the adjacent positive and negative plates. The external fixing frame 1 is a steel frame and is fixed on two sides of the module, and is tensioned and fixed through a plurality of tensioning rods 3 arranged circumferentially.

The positive plate and the negative plate are arranged between the external fixing frames 1 at intervals, the two electrode plates 2 are made of bipolar membrane materials, namely, the bipolar membrane materials can be used as electrodes in a conductive mode, meanwhile, a permeation effect can be achieved, and a plurality of groups of electrodes can be formed in a single partition electrodialysis module to be used.

The single-pole partition board 4 is a main electrodialysis concentration part, a plurality of cavities are arranged between the single-pole partition board and are connected with a liquid supply pipeline for liquid preparation. The high-salt sewage treated in the embodiment enters the cavity between each of the monopole partition boards 4 from the lower part through the liquid supply pipeline, forms a power source for directional movement of ions by the two groups of electrodes, attracts the ions to move directionally, and is limited by the monopole partition boards 4 with different polarities, so that a plurality of concentration tanks and clean water tanks are formed in the monopole partition boards 4 between the two groups of electrode boards 2 at intervals.

Specifically, the monopolar separator 4 is provided with a volume groove 5 which is open towards one side, an ion exchange membrane is arranged at the bottom of the volume groove 5, the polarities of the ion exchange membranes on the adjacent monopolar separators 4 are opposite, and the volume groove 5 is communicated with the liquid supply pipeline to realize liquid flow; the monopole partition plates 4 are provided with hard pressing strips, and the pressing strips are matched with the edges of the volume grooves 5 to be pressed tightly so as to realize sealing.

The batten is made of hard material relative to the monopole separator 4, and is generally arranged on a sheet body with a larger area, and the batten is arranged between adjacent monopole separators 4 to form an effect. The other parts of the sheet body where the pressing strips are positioned are contacted with the surfaces of other volume removing grooves 5 of the monopole partition plate 4, and are clamped by an external fixing frame 1 and are attached and fixed with the monopole partition plate 4.

Further, the monopolar separator 4 has a soft deformation zone near the edge of the volume groove 5, and the pressing strip has a portion pressing the deformation zone when the several monopolar separators 4 are buckled and contacts at least 40% of the deformation zone by the portion to press the deformation seal. The deformation region is a region where the hardness of the material is lower than that of the pressing strip, and has certain elastic deformation performance, so that when the pressing strip is completely pressed, the deformation region deforms to fill gaps of the deformation region, and the sealing effect is achieved.

In a general embodiment, the monopolar separator 4 is made of PP/PT material, and has a thickness of 4-20mm and does not have good elastic deformation performance. Then, in the production, it is necessary to form the volume groove 5 first, then form an empty region at a position near the edge of the volume groove 5, and then fill the empty region with the deformed region. The specific implementation mode is as follows:

in some embodiments, the monopole baffle plate 4 is provided with a sinking groove between the edge of the volume groove 5 and the edge of the monopole baffle plate 4, and the deformation area is soft insulating material filled in the sinking groove; when the monopole partition plates 4 are buckled, the pressing strips penetrate into the sinking grooves to squeeze the deformation areas, and the contact area between the pressing strips and the deformation areas is 40% -70%. This way, a better sealing effect can be achieved, and less material is required, but the manufacturing process is more difficult due to the smaller thickness of the separator.

Experiments show that under the conditions of the thickness and the material of the monopole partition board 4 with the existing thickness, the contact area is smaller than 40%, the water leakage rate of the combined concentration module is larger than 20%, the use requirement is not met, the analysis is that the fact that the contact area is smaller results in even alignment and placement during manual assembly, but the fact that the smaller contact area cannot ensure that extrusion sealing can be formed on the whole pressing strip on the premise of larger unfolding area is achieved. After the contact area is larger than 70%, the resistance of the single-pole partition plates 4 is larger during extrusion, gaps are easily generated during assembly due to larger elastic feedback force, and the water leakage rate is increased too and cannot meet the requirements.

In some embodiments, as shown in fig. 8 and 9, the local structures of two adjacent monopole separators 4 at the edges of the volume groove 5 are shown, the specific range of the deformation area is not shown, the deformation area is the area where the edges of the volume groove 5 form a drop, and the contact area of the pressing strip and the deformation area is 50-80%; when the monopole partition plates 4 are buckled, the outer side edge of the pressing strip does not exceed the outer side of the deformation area, the inner side edge of the pressing strip is positioned in the volume groove 5, and the thickness of the pressing strip is smaller than the depth of the volume groove 5.

Further, as shown in fig. 10, the deformation area has a first inclined plane, the pressing bar has a second inclined plane corresponding to the deformation area, and the first inclined plane contacts with the second inclined plane when the pressing bar presses the deformation area. The two inclined planes are contacted, so that larger contact area can be realized under the limited width, meanwhile, due to the symmetrical arrangement, the pressing strips on the two sides of the volume groove 5 can realize a certain pre-positioning effect, and the direct pressing mode is adopted to form the side of the volume groove 5, so that the volume groove 5 can be aligned better.

In some embodiments, the deformation area is a sealing strip 11 arranged at the inner bottom of the volume groove 5 and close to the edge of the volume groove 5, and when the monopole partition plates 4 are buckled, the pressing strip is completely sunk into the volume groove 5 and is in contact extrusion with the sealing strip 11, and the contact area of the pressing strip and the surface of the sealing strip 11 is 40-50%. The gap between the pressing strip and the bottom in the volume groove 5 when the monopole partition plates 4 are buckled is d, and the height of the sealing strip 11 is 2d and is smaller than the depth of the volume groove 5.

The height of the sealing strip 11 is limited to avoid that the sealing strip 11 attached to the side edge of the volume groove 5 cannot deform to the middle part of the volume groove 5 after being extruded by the pressing strip, so that the elastic resistance is larger.

The monopole partition plates 4 are plate bodies made of soft materials, hard plate layers are arranged between adjacent monopole partition plates 4, and the pressing strips are arranged on the hard plate layers.

The monopole clapboard 4 is of a multi-layer structure and at least comprises a soft interlayer 4.1 and a hard board layer 4.2, the volume groove 5 is an opening in the middle of the soft interlayer 4.1, the hard board layer 4.2 is provided with a plurality of through holes at the opening of the soft interlayer 4.1, and the ion exchange membrane is attached to the through holes and fixed by edge sealing of the soft interlayer 4.1; the bead is arranged on the hard plate layer 4.2 and protrudes in the opposite direction to the volume groove 5.

The monopole partition plate 4 is provided with a plurality of water permeable holes which are centrally symmetrical at two sides of the volume groove 5, the water permeable holes at one side comprise a first water permeable hole 6 and a second water permeable hole 7 which are arranged at intervals, wherein the second water permeable hole 7 is provided with a plurality of diversion fine grooves 8 communicated with the edge of the adjacent side of the volume groove 5, and the edge of one side of the volume groove 5 is divided into a plurality of short sides by the diversion fine grooves 8 which are arranged at intervals; the pressing strips comprise long pressing strips 9 corresponding to the adjacent edges of the volume grooves 5 and not pressed with the water permeable holes, and short pressing strips 10 corresponding to a plurality of short sides of the volume grooves 5; the end part of the long pressing strip 9 is provided with an expansion end, and a deformation area corresponding to the expansion end is arranged on the soft interlayer 4.1.

It should be noted that, unlike the prior art, the area of the water permeable hole is smaller, and the possibility of water leakage does not exist after the water permeable hole is attached. The side edge of the volume groove 5 without the water permeable hole has a longer length, and the width of the volume groove is narrower due to the fact that the volume groove is closer to the edge of the whole monopole partition plate 4, so that deformation water leakage is more easy to occur. Therefore, the long pressing strip 9 is arranged on the longer side of the sealing strip to press and seal the whole side, and even if the side is deformed locally, the water leakage from the deformed part can be prevented.

The deformed portion of the monopolar separator 4 means that the soft separator 4.1 of PP material is folded when being assembled, and water leakage occurs at the folded position.

And the permeable hole is especially arranged between the diversion fine grooves 8, as the diversion fine grooves 8 are provided with a plurality of groups, the deformation resistance of the material in the area is lower, and the side edge of the volume groove 5 between the two diversion fine grooves 8 is easy to form extrusion deformation during extrusion, so that the area is covered with the extrusion deformation through the short pressing strip 10, thereby meeting the actual requirement and ensuring that the diversion fine grooves 8 are not blocked due to the pressing strip.

The invention is not limited to the alternative embodiments described above, but any person may derive other various forms of products in the light of the present invention. The above detailed description should not be construed as limiting the scope of the invention, which is defined in the claims and the description may be used to interpret the claims.

Claims (10)

1. A bipolar membrane electrodialysis concentration system comprises a partition electrodialysis module, a liquid supply pipeline and an electric control system, wherein the liquid supply pipeline and the electric control system are respectively connected with the partition electrodialysis module, the liquid supply pipeline is connected with the partition electrodialysis module for liquid introduction/export, and the electric control system is connected with the partition electrodialysis module for power supply; the method is characterized in that:

the partition electrodialysis module comprises a fixed structure and an electrode plate (2), wherein the electrode plate (2) comprises a plurality of positive plates and negative plates which are paired and connected with an electric control system, and a plurality of unipolar partitions (4) are arranged between the adjacent positive plates and negative plates;

the monopolar separation plates (4) are provided with volume grooves (5) which are open towards one side, the inner bottoms of the volume grooves (5) are provided with ion exchange membranes, the polarities of the ion exchange membranes on the adjacent monopolar separation plates (4) are opposite, and the volume grooves (5) are communicated with the liquid supply pipeline to realize liquid flow;

a hard pressing strip is arranged between the monopole partition plates (4), and the pressing strip is matched with the edge of the volume groove (5) to be pressed tightly to realize sealing.

2. A bipolar membrane electrodialysis concentration system according to claim 1, wherein: the monopole partition plates (4) are provided with soft deformation areas near the edges of the volume grooves (5), and the pressing strips are provided with parts for extruding the deformation areas when the monopole partition plates (4) are buckled and contact with at least 40% of the deformation areas for extrusion deformation sealing.

3. A bipolar membrane electrodialysis concentration system according to claim 2, wherein: the monopole clapboard (4) is provided with a sinking groove between the edge of the volume groove (5) and the edge of the monopole clapboard (4), and the deformation area is soft insulating material filled in the sinking groove;

when the monopole clapboards (4) are buckled, the pressing strips penetrate into the sinking grooves to squeeze the deformation areas, and the contact area between the pressing strips and the deformation areas is 40% -70%.

4. A bipolar membrane electrodialysis concentration system according to claim 2, wherein: the deformation area is an area with a drop formed by the edge of the volume groove (5), and the contact area of the pressing strip and the deformation area is 50-80%;

when the monopole clapboards (4) are buckled, the outer side edge of the pressing strip does not exceed the outer side of the deformation area, the inner side edge of the pressing strip is positioned in the volume groove (5), and the thickness of the pressing strip is smaller than the depth of the volume groove (5).

5. A bipolar membrane electrodialysis concentration system according to claim 4, wherein: the deformation area is provided with a first inclined plane, the pressing strip is provided with a second inclined plane corresponding to the deformation area, and the first inclined plane is contacted with the second inclined plane when the pressing strip presses the deformation area.

6. A bipolar membrane electrodialysis concentration system according to claim 2, wherein: the deformation area is a sealing strip (11) which is arranged at the inner bottom of the volume groove (5) and is close to the edge of the volume groove (5), the pressing strip is completely sunk into the volume groove (5) and is in contact extrusion with the sealing strip (11) when a plurality of monopole partition boards (4) are buckled, and the contact area between the pressing strip and the surface of the sealing strip (11) is 40-50%.

7. A bipolar membrane electrodialysis concentration system according to claim 6, wherein: the gap between the pressing strip and the bottom in the volume groove (5) is d when the monopole partition plates (4) are buckled, and the height of the sealing strip (11) is 2d and is smaller than the depth of the volume groove (5).

8. A bipolar membrane electrodialysis concentration system according to any one of claims 2-7, wherein: the monopole partition plates (4) are plate bodies made of soft materials, hard plate layers are arranged between adjacent monopole partition plates (4), and pressing strips are arranged on the hard plate layers.

9. A bipolar membrane electrodialysis concentration system according to any one of claims 2-7, wherein: the monopole clapboard (4) is of a multilayer structure and at least comprises a soft interlayer (4.1) and a hard board layer (4.2), the volume groove (5) is an opening in the middle of the soft interlayer (4.1), the hard board layer (4.2) is provided with a plurality of through holes at the opening of the soft interlayer (4.1), and the ion exchange membrane is attached to the through holes and fixed by edge sealing of the soft interlayer (4.1);

the pressing strip is arranged on the hard plate layer (4.2) and protrudes towards the opposite direction of the volume groove (5).

10. A bipolar membrane electrodialysis concentration system according to claim 9, wherein: the monopole baffle plate (4) is provided with a plurality of water permeable holes which are centrally symmetrical at two sides of the volume groove (5), the water permeable holes at one side comprise a first water permeable hole (6) and a second water permeable hole (7) which are arranged at intervals, the second water permeable hole (7) is provided with a plurality of diversion fine grooves (8) communicated with the edges of the adjacent sides of the volume groove (5), and the edges of one side of the volume groove (5) are separated into a plurality of short sides by the diversion fine grooves (8) which are arranged at intervals;

the pressing strips comprise long pressing strips (9) corresponding to the volume grooves (5) and not pressed with the adjacent edges of the water permeable holes, and short pressing strips (10) corresponding to the short sides of the volume grooves (5);

the end part of the long pressing strip (9) is provided with an expansion end, and a deformation area corresponding to the expansion end is arranged on the soft interlayer (4.1).

Images